Spectral Domain Optical Coherence Tomography findings in idiopathic lamellar macular hole

BACKGROUND: To evaluate demographic, functional, and morphological parameters of idiopathic lamellar macular hole (ILMH). METHODS: Observational longitudinal retrospective study. Optical coherence tomography examinations and corresponding clinical charts of a series of consecutive patients affected by ILMH, between January 2010 and March 2015, from the database of the Department of Ophthalmology of Trento Hospital, Italy, have been collected and examined. Demographic and functional parameters were: age (year), gender (male/female), eye (right/left), lens status, best-corrected visual acuity (BCVA) in logarithm of the minimum angle of resolution (LogMAR). Tomographic parameters were: LMH shape pattern (intraretinal splitting LMH, IR split LMH, and V-shaped LMH, V LMH), posterior vitreous detachment (PVD yes/ PVD no), ERM type (conventional ERM and atypical ERM), integrity of ellipsoid zone (EZ) and external limiting membrane (ELM), residual foveal thickness (RFT) micron (μ), maximal diameter of intraretinal splitting (MDIRS) (μ). RESULTS: One hundred and eighty-nine eyes of 175 patients were included. The mean age was 72.84 ± 9.6, range 41-96 years. BCVA mean was 0.24 ± 0.25, range 0 -1.3 LogMAR. One hundred and forty-one eyes (74.6 %) were affected by IR split LMH, 48 eyes (25.4 %) were affected by V LMH. Every cases of ILMH were associated with ERM: 117 (61.9 %) conventional ERM, 72 (38.1 %) atypical ERM. A significant prevalence of female gender, phakic condition, and PVD in conventional ERM ILMH subgroup (P = 0.000) was found. BCVA mean was better in the conventional ERM ILMH subgroup (P = 0.000). An association between the interruption of the outer retinal layers (EZ and ELM) and atypical ERM ILMH subgroup was highlighted (P = 0.000). The statistical analysis showed a correlation between BCVA and integrity of ELM (P = 0.000). RFT significantly decreased in atypical ERM ILMH subgroup at 24 months compared to time point 0 (P = 0.027). A progressive increase of MDIRS in both subgroups at 12 months and in atypical ERM ILMH subgroup at 24 months (P = 0.007) was highlighted. CONCLUSIONS: This study demonstrated that ILMH was not a stable condition, showing morphological changes and an involvement of the outer retinal layers during the 2 years of follow-up.